1. Field
Exemplary embodiments relate to a method of manufacturing an LC circuit, which forms a metal-insulator-metal (MIM) capacitor under a metal-interconnection type inductor coil to use a MIM top routing metal as the inductor coil, and more specifically, to a method for manufacturing an LC circuit, which includes installing a capacitor under an inductor to reduce the overall area of a radio-frequency integrated circuit (RF IC) in which passive elements such as inductors and capacitors occupy the largest area. The capacitor is formed in such a manner that the width of metal interconnections of the inductor is equal to or smaller than that of the MIM capacitor, in order for the capacitor not to degrade the characteristics of the inductor.
2. Description of Related Art
As the paradigm of the information communication field changes, a communication scheme independent of time and place is being demanded. A wireless communication field is the most suitable field for such a demand, and has been rapidly developing. With the development of wireless communication, radio-frequency resources are needed, and demand for materials, elements, and circuits operating at radio frequencies is increasing. Since they are used at radio frequencies, they are generally classified into RF parts and ICs.
The RF IC technology may be accomplished through a combination of device manufacture technology, circuit design technology and radio-frequency package technology. In order to develop competitive RF-CMOS devices, the respective technologies should develop harmoniously. The RF-CMOS devices mainly include a RF metal oxide semiconductor field effect transistor (RF MOSFET), an inductor, a varactor, a capacitor, and a resistor.
In particular, the inductor may be used for constructing a radio frequency chip, but may occupy the largest portion of the area of the radio frequency chip as a single device. The inductor may be formed in a rectangular type, octagonal type, or circular type. The inductance of the inductors may be improved more or less depending on the shapes thereof. However, it is difficult to deny that the inductor occupies a large area in the radio frequency chip, regardless of which shape the inductor has.